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Division of Spill Prevention and Response


Updated: Sep. 29, 2016




What are the Risks?
Recommendations from the Alaska Department of Health and Social Services
Disclosure of Contamination in Property Sales and Rentals
Additional Resources




This Notice to the public provides information about areas of contaminated groundwater in and nearthumbnail map of study area - sulfolane contamination North Pole, Alaska. Releases of sulfolane at the former North Pole Refinery (NPR) contaminated the groundwater throughout much of the City of North Pole and beyond the city boundaries.  The sulfolane contamination affects many residents, homeowners and landowners and is expected to remain in the groundwater for many years. The area of groundwater carrying sulfolane is approximately 2 miles wide, 3.5 miles long and over 300 feet deep, making it one of the largest areas of contaminated groundwater in the state. (See maps page.


ADEC actively oversees Flint Hills’ actions regarding the groundwater contamination. (See Project History page for detailed information.) This Groundwater Notice is intended to help ensure that the affected community is aware of the contamination and appropriate safety precautions.


Specific purposes of this Groundwater Notice are to:

  • Notify land owners, tenants, businesses, residents, real estate agents, and prospective property buyers of the contaminated groundwater;
  • Provide information to help the community understand the contamination and its implications; and
  • Protect the communities from exposure to contamination.


To avoid exposure to contamination in the areas covered by this Notice, please contact ADEC prior to installing any water wells or digging excavations that could encounter groundwater. For additional information, please contact ADEC at (907) 451-2143.


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What are the Risks?


Drinking water contaminated with sulfolane presents the biggest risk associated with the groundwater contamination. Since the 2009 discovery of sulfolane in drinking water wells, Flint Hills has been providing water to affected homes and businesses with any detections of sulfolane. In addition, Flint Hills is providing interim bottled water to properties in a “buffer zone” outside of the area of sulfolane contamination. If your water is delivered to a tank or if you are connected to city water, you are not at risk of drinking sulfolane contaminated water. If you are being provided bottled water, you are not at risk of drinking contaminated water. If you have and maintain a home treatment system your water is safe to drink.


Common ways in which properties sulfolane may be impacted by the sulfolane groundwater contamination are described below, along with measures that can be taken to prevent exposure to the sulfolane.

Possible impacts to properties within the sulfolane plume

Well Water On many properties in the North Pole area, wells drilled into the ground provide water for drinking, cooking, showering, gardening, etc. If your well taps into contaminated groundwater and you are not using a home treatment system, then your water supply may be contaminated with sulfolane.  

Flint Hills has addressed contaminated well water in the sulfolane plume by adding a home treatment system to remove the sulfolane or by supplying a different source of drinking water, such as water delivery to a tank or connection to city water, where available. Currently, Flint Hill is offering bottled water supplies to affected properties.

If you live in the area of the plume and have concerns about your water, contact Flint Hills’ Groundwater Office at (907) 488-0723 or
Indoor Air Sulfolane does not vaporize into air and therefore does not present a risk to the indoor air of homes and buildings.
Bringing subsurface contamination
above ground

Excavations, washing cars, and watering lawns and gardens are ways to bring sulfolane to the surface and possibly cause exposure.  However, because sulfolane does not vaporize into air, nor does it stick to soil, washing cars and watering lawns will not cause signifcant exposure to sulfolane.  


Vegetables irrigated with water containing sulfolane have been shown to take up sulfolane. North Pole residents are encouraged to follow the DHSS recommendations regarding edible plants that are summarized in the next section. 

Excavations for development and utility maintenance frequently require dewatering to lower the water table in support of the construction activity. Special permit conditions apply for dewatering conducted close to contaminated sites. If dewatering is needed within 1,500 feet of areas covered by this Groundwater Notice, please follow this link for more information.

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Recommendations from the Alaska Department of Health and Social Services


Currently, there is little information on the health effects of sulfolane on humans. What we do know about the toxicity of the solvent comes from laboratory studies where test animals were exposed to relatively high levels of sulfolane for short periods of time (up to six months). We hope to gain a better understanding of sulfolane’s toxicity in the next 4-5 years, as the federal National Toxicology Program is currently conducting animal studies to evaluate the short- and longer term health effects of sulfolane.


These are the current recommendations from the Alaska Department of Health and Social Services:

Residents who have wells with sulfolane detections should continue using an alternative water supply for drinking and for growing edible plants. Edible garden plants can take up sulfolane from water, therefore people can be exposed to sulfolane by consuming produce that has been watered with sulfolane-contaminated water.

Given the concentrations of sulfolane reported to date, residents can still use wells with positive sulfolane detections for most household activities such as bathing, washing clothes and dishes, rinsing foods, and making foods where the water is discarded, such as boiling eggs. Based on currently available information, using well water to shower does not pose a health risk for North Pole residents, although inhaling sulfolane in water droplets during showering needs further evaluation.

Other exposure routes such as breathing vapors or direct skin contact are unlikely to pose a risk because the chemical has low volatility and is not absorbed through the skin.

Residents on the city’s public water system are encouraged to use city water for gardening.

Residents who raise chickens or other animals do not have to worry about sulfolane in their meat or other products (milk, cheese, eggs, etc.) as long as the animals are not drinking water that contains sulfolane.

For a more complete discussion on health implications and current research, please see our Human Health and Toxicology page.


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Disclosure of Contamination in Property Sales and Rentals


Sale of residential property:  Alaska law requires that, during the sale of residential property, any environmental hazard must be disclosed to a prospective buyer before completing the sale (Alaska Statute (AS) 34.70.010). Disclosure forms are available through the following link on the Alaska Real Estate Commission's website.

Sale of commercial or industrial property:  Prospective purchasers are encouraged to hire environmental professionals to perform Phase I/II Environmental Site Assessments (ESA). The American Society for Testing Materials (ASTM) has developed the industry’s Standard Practice for Environmental Site Assessments; it is available for purchase at this link

Landlords and Tenants: Property owners who are landlords and provide rental properties to tenants should use reasonable care to inform tenants and provide remedies for environmental hazards as outlined in the Alaska Uniform Residential Landlord and Tenant Act (AS 34.03.010 – 34.03.360), and must supply clean and reliable water and safe and habitable living conditions. For more information, please consult the Department of Law's website and their publication "The Alaska Landlord & Tenant Act: What it means to you." Note: this law and the supporting document are both subject to change.  To request a copy of the booklet, call (907) 269-5200 or toll free (888) 576-2529. You can also email your request to

For more information on sulfolane contaminated groundwater, please contact ADEC’s Contaminated Sites Program at (907) 451-2143.

You may seek the service of an environmental professional to evaluate the nature of contamination and any potential risks associated with the specific property under consideration. See Hiring an Environmental Consultant.


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Additional Resources



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